Apple has applied for a patent for a technology that places solar power cells under a touch screen, according to Free Patents Online.

Such a device could overcome one of the primary obstacles for using solar power on mobile devices - simply finding enough space on the device for large enough cells. This could potentially result in an iPod or iPhone that can be used indefinitely under direct sunlight without needing to be plugged in for a recharge.

Several other companies, such as Nokia and Vodafone, have recently expressed increasing interest in "Going Green" using technologies like solar power. In addition to the potential for increased convenience, the use of solar cells in Apple's devices could reduce the company's overall carbon footprint, which would ultimately make it a huge benefit not only to consumers but also to the environment as a whole.